[Astell&Kern] CA1000 Portable Headphone Amp

The ACRO CA1000 is a headphone amplifier that combines the functions and portability of a high-performance amplifier and DAP based on Astell&Kern's fundamental philosophy of delivering original sound, and it sets a new standard for headphone amplifiers, providing powerful and clear sound with the features never available on any other headphone amplifiers.

The CA1000 supports a four-step Gain Level setting that can run high-impedance headphones with a 15Vrms (Condition No Load) output level - without deterioration of sound quality. The ACRO CA1000 can accommodate a wide variety of headphones ranging from balanced 2.5mm and 4.4mm to unbalanced 3.5mm and 6.35mm outputs.

With a pedigree of designing and engineering award-winning premium DAPs, Astell&Kern knowledge of DAC technology is unprecedented. The ACRO CA1000 arrives with a high-quality, high-performance Quad ES9068AS DAC that delivers a clear, detailed and balanced sound without distortion. The Quad-DAC also supports high-resolution audio playback up native DSD512 and 32 bit/384 kHz, enabling the music fan to get even closer to the original studio sound, while revealing musical details never heard before.

Following on from the A&futura SE180 player, the CA1000 is the third model to adopt Astell&Kern’s patented TERATON ALPHA Sound Solution. The result of extensive research and development, it is designed to deliver audio playback close to the original sound. The onboard DAC is not the only factor that determines the quality of sound from a DAP: Power, noise, signal conversion, and circuit structure, all will affect the sound signature. Only when each and every one of these elements is optimized, can a player produce sound as close as the music artist and producer intended. TERATON ALPHA technology, effectively removes power noise and provides efficient power consumption and amplification right through to the audio output interface stage where the digital-to-analogue signal conversion (DAC) takes place – audio technology Astell&Kern has consistently developed and perfected over the years.

In a headphone environment where the left and right channels are clearly separated, ear fatigue can increase when listening over long periods. Activate the Crossfeed function and a more comfortable listening experience is revealed. This mode has the effect of blending the left and right channels, relieving ear fatigue by creating a more natural sound akin to listening to speakers. In this setting Shelf Cutoff, Shelf Gain, and Mixer Levels are adjustable according to listening tastes.

More than just a powerful headphone amp, the ACRO CA1000 also features DAP capabilities, transforming it into the go-to-system for head-fi aficionados. A titling 4.1-inch touchscreen (up to 60-degrees) enables easy control of the player and amp settings with an intuitive Android OS and feature set taken from its award-winning portable DAPs. Although not entirely mobile as an Astell&Kern DAP, this amp player hybrid system is compact and portable. Equipped with an 8,400mAh large capacity battery, the ACRO CA1000 can provide up to 10 hours playback without a separate power supply. An array of inputs and outputs allows connection of digital and analogue sources to expand the systems capabilities. These include Optical, Coaxial, Type-C USB digital inputs/outputs and RCA analog input/output (RCA).

A BT Sink function connects the ACRO CA1000 to an external device, such as a smartphone, via Bluetooth, enabling music to be played back in high-quality on the headphone amp. Elsewhere the ACRO CA1000 boasts Bluetooth® 5.0, providing greater range and a more stable wireless connection to headphones and, along with support for 24-bit aptX™ HD and LDAC codecs, offers the best possible wireless sound quality. Alongside dual-band Wi-Fi support, the ACRO CA1000 features AK File Drop for easier wireless file transfers. Users can wirelessly transfer files through a PC, smartphone, or FTP program located on the same network to make music management even more convenient.

General Specifications:
Colour: Moon Silver
Housing Material: Aluminum
Display: 4.1inch HD 720 x 1280 Touch Display
Supported Format: WAV, FLAC, WMA, MP3, OGG, APE, AAC, ALAC, AIFF, DFF, DSF, MQA
Sampling Rate:
PCM: 8kHz ~ 384kHz (8/16/24/32bits per Sample); DSD Native: DSD64 (1bit 2.8MHz), Stereo / DSD128(1bit 5.6MHz), Stereo / DSD256(1bit 11.2MHz), DSD512(1bit, 22.4MHz) Stereo
Output Level:
Super: Unbalanced 8Vrms │ Balanced 15Vrms (Condition No Load)
High: Unbalanced 6Vrms │ Balanced 12Vrms (Condition No Load)
Mid: Unbalanced 4Vrms │ Balanced 8Vrms (Condition No Load)
Low: Unbalanced 2Vrms │ Balanced 4Vrms (Condition No Load)
CPU: Quad-Core
Digital to Analog Converter (DAC): ESS ES9068AS x4 (Quad DAC)
Supported Audio: Support up to 32 bit/ 384kHz Bit to Bit playback
Headphone Output: Unbalanced (3.5mm, 6.35mm) / Balanced (2.5mm, 4.4mm)
Analog I/O:
RCA (Stereo pair) x1
RCA (Stereo pair) x1
Digital I/O:
Coaxial x1, Optical x1, USB (Type-C) x1
Optical (3.5mm) x1, USB (Type-C) x1
Wi-Fi: 802.11 a/b/g/n/ac (2.4/5GHz)
Bluetooth: V5.0 (A2DP, AVRCP, Qualcomm® aptX™ HD, LDAC)
Dimension and Weight: 4.12"(104.9mm)[W] x 1.77"(45mm)[H] x 5.85"(148.8mm)[D]，～919g
Charging Time: about 2.5 hours (9V / 3A PD2.0 Fast Charging) | 7 hours (5V 2A General Charging)
Storage: 256GB [NAND]
Supported External Storage: microSD x1 (Max. 1TB)
Battery: 8,400mAh 3.8V Li-Polymer
Playback Time: about 10.5 hours (Standard: FLAC, 16bit, 44.1kHz, Unbalanced, Vol.40, LCD Off, Low Gain)

Audio Specifications:
Frequency Response:
±0.024dB (Condition : 20Hz~20kHz) Unbalanced
±0.018dB (Condition : 20Hz~20kHz) Balanced
±0.048dB (Condition : 20Hz~20kHz) RCA
±0.059dB (Condition : 20Hz~70kHz) Unbalanced
±0.056dB (Condition : 20Hz~70kHz) Balanced
±0.048dB (Condition : 20Hz~70kHz) RCA
Signal-Noise Ratio (SNR) : 0.005% @ 1kHz, Unbalanced / 0.002% @ 1kHz, Balanced / 0.0004% @ 1kHz, RCA
Crosstalk: -105dB @ 1kHz, Unbalanced / -124dB @ 1kHz, Balanced / -121dB @ 1kHz, RCA
THD+N: 0.0003% @ 1kHz, Unbalanced │ 0.0005% @ 1kHz, Balanced
IMD SMPTE:
0.0008% 800Hz 10kHz (4:1) Unbalanced
0.0004% 800Hz 10kHz (4:1) Balanced
0.0003% 800Hz 10kHz (4:1) RCA
Impedance: 3.5mm, 6.35mm (1ohm), 2.5mm, 4.4mm (2ohm), RCA (2ohm)
Clock Source: 25ps (Typ)｜Ref 70p